Exhaust gases and/or compressed air from aircraft engines can be used for many purposes. Exhaust gases can be ported to drive impellers of pneumatic motors to provide energy. These impeller driven motors may perform various mechanical functions, such as generate electricity, pump gases, rotate shafts, etc. Exhaust gases can be ported to provide heat in locations remote from the aircraft's engines. Exhaust gases can be used as part of a temperature regulation system to maintain an atmospheric environment in temperature sensitive locations of an aircraft. Compressed air can be used for cabin pressurization or as a source for pneumatic control systems.
Both the exhaust gases and the compressed air can be very hot, as exhaust gases are the product of an exothermic chemical reaction, and pressurization raises the temperature of the air being compressed. Various plenums, manifolds, and ductworks can be used to route these exhaust gases from the engines to the various locations of the aircraft that require their use. It may be desirable, to localize the high temperature of the gases to locations immediately surrounding these plenums, manifolds and ductworks. Should these plenums, manifolds, and ductworks fail so as to permit the exhaust gases and/or compressed air to leak, deleterious effects may arise.
Linear thermal sensors can be located adjacent to and along these plenums, manifolds, and ductworks that carry hot exhaust gases and/or compressed air. Such linear thermal sensors can provide a monitoring function of the temperature immediately adjacent to the plenums, manifolds, and ductworks at locations traversed by the linear thermal sensors. Should these linear thermal sensors indicate a temperature at a specific location that is greater than a predetermined threshold, pilots of the aircraft can be notified as to the sensed over-temperature condition.
Linear thermal sensors can be used in various locations besides aircraft. For example, linear thermal sensors can be used in ground-based, marine, and/or aerospace applications. These sensors are particularly useful if detection of overheat events is required along a linear path. Known methods for testing linear thermal sensors yield less than optimal results. And known systems that interface with linear thermal sensors and sensor arrays have encountered difficulties in detecting thermal events beyond a first electrical discontinuity.